This invention relates to controllers for antenna rotators and conversion systems for antenna rotator controllers.
Antenna rotators include antenna position sensors, typically a potentiometer which has a voltage applied thereto, for producing an analog signal representative of the heading or angular position antenna. The analog signal is supplied to an antenna rotator controller with a deflecting meter having a scale calibrated in degrees, or it may be converted to a digital signal for a digital display of the antenna heading with relation to a fixed reference heading (e.g., degrees relative to a South reference).
Antenna rotators generally have stops limiting their travel to approximately one revolution to prevent damage to cables connected to the antenna. It is often undesirable for the stop to be at due North, which correlates with a South Center fixed reference heading. For example, to change the heading of an antenna situated in central United States from Europe (Northeast) to Asia (Northwest) will require approximately 270.degree. of rotation if the stop is at due North. If, however, the rotator stop is at due South (which correlates with a North Center fixed reference heading) only a 90.degree. change in heading is required thereby reducing the time required to change the antenna heading from northeast to northwest. Thus many users or operators of antenna controllers may want a fixed reference heading different from whichever one is provided by the manufacturer.
Not only is it advantageous for an antenna controller to provide the user with two different selectable reference headings, but it is also desirable to enable the users of many existing antenna controllers to convert them inexpensively and conveniently so as to have two selectable reference headings and to provide a digital display to replace the original deflecting meter type of analog display of headings.